Contemporary accuracy of death certificates for coding prostate cancer as a cause of death: Is reliance on death certification good enough? A comparison with blinded review by an independent cause of death evaluation committee.

BACKGROUND: Accurate cause of death assignment is crucial for prostate cancer epidemiology and trials reporting prostate cancer-specific mortality outcomes. METHODS: We compared death certificate information with independent cause of death evaluation by an expert committee within a prostate cancer trial (2002-2015). RESULTS: Of 1236 deaths assessed, expert committee evaluation attributed 523 (42%) to prostate cancer, agreeing with death certificate cause of death in 1134 cases (92%, 95% CI: 90%, 93%). The sensitivity of death certificates in identifying prostate cancer deaths as classified by the committee was 91% (95% CI: 89%, 94%); specificity was 92% (95% CI: 90%, 94%). Sensitivity and specificity were lower where death occurred within 1 year of diagnosis, and where there was another primary cancer diagnosis. CONCLUSIONS: UK death certificates accurately identify cause of death in men with prostate cancer, supporting their use in routine statistics. Possible differential misattribution by trial arm supports independent evaluation in randomised trials.

Predicting high-grade cancer at ten-core prostate biopsy using four kallikrein markers measured in blood in the ProtecT study.

BACKGROUND: Many men with elevated prostate-specific antigen (PSA) levels in serum do not have aggressive prostate cancer and undergo unnecessary biopsy. Retrospective studies using cryopreserved serum suggest that four kallikrein markers can predict biopsy outcome. METHODS: Free, intact and total PSA, and kallikrein-related peptidase 2 were measured in cryopreserved blood from 6129 men with elevated PSA (≥3.0ng/mL) participating in the prospective, randomized trial Prostate Testing for Cancer and Treatment. Marker levels from 4765 men providing anticoagulated plasma were incorporated into statistical models to predict any-grade and high-grade (Gleason score ≥7) prostate cancer at 10-core biopsy. The models were corrected for optimism by 10-fold cross validation and independently validated using markers measured in serum from 1364 men. All statistical tests were two-sided. RESULTS: The four kallikreins enhanced prostate cancer detection compared with PSA and age alone. Area under the curve (AUC) for the four kallikreins was 0.719 (95% confidence interval [CI] = 0.704 to 0.734) vs 0.634 (95% CI = 0.617 to 0.651, P < .001) for PSA and age alone for any-grade cancer, and 0.820 (95% CI = 0.802 to 0.838) vs 0.738 (95% CI = 0.716 to 0.761) for high-grade cancer. Using a 6% risk of high-grade cancer as an illustrative cutoff, for 1000 biopsied men with PSA levels of 3.0ng/mL or higher, the model would reduce the need for biopsy in 428 men, detect 119 high-grade cancers, and delay diagnosis of 14 of 133 high-grade cancers. Models exhibited excellent discrimination on independent validation among men with only serum samples available for analysis. CONCLUSIONS: A statistical model based on kallikrein markers was validated in a large prospective study and reduces unnecessary biopsies while delaying diagnosis of high-grade cancers in few men.

Gleason drift in the NIHR ProtecT study.

AIMS: There is increasing evidence of Gleason score (GS) drift in prostatic core biopsies during the last two decades. The ProtecT study is a randomized controlled study and provides an excellent cohort to study the effect of time, prostate-specific antigen (PSA) level, perineural invasion, tumour length and age on GS. METHODS AND RESULTS: The ProtecT study recruited men in the United Kingdom between 1999 and 2010. The Gleason scores were grouped into four categories ≤ 3 + 3, 3 + 4, 4 + 3 and ≥ 4 + 4 for analysis. Data from England between 2000 and 2012 were also available. A total of 3282 biopsies containing cancer were analysed. For each year of the ProtecT study, the odds of being diagnosed with a higher GS category increased by 4.9%. Higher GS was also associated with perineural invasion, increasing tumour length, age and PSA level. While biopsy GS from England was incomplete, it also showed a marked decrease in GS five and six tumours during the same period. CONCLUSION: There was GS drift from 3 + 3 to 3 + 4 with time in the ProtecT study, but there appeared to be no significant change in percentage of GS 4 + 3 or higher. This drift was less dramatic when compared to GS in the rest of England.

Alteration in urinary matrix metalloproteinase-9 to tissue inhibitor of metalloproteinase-1 ratio predicts recurrence in nonmuscle-invasive bladder cancer.

PURPOSE: The purpose is to assess the prognostic significance of matrix metalloproteinase (MMP)-9 in patients with bladder cancer using a combination of ELISA (to measure MMP-9 in voided urine) and immunohistochemistry (to study MMP-9 in bladder tumors). The relationship between MMP-9 and its principal inhibitor, tissue inhibitor of metalloproteinase (TIMP)-1 (in voided urine samples) was also studied. EXPERIMENTAL DESIGN: A total of 134 patients with bladder tumors (7 cis, 76 T(a), 27 T(1), 24 T(2)-T(4); 40 G1, 43 G2, and 44 G3), 33 patients with benign urological conditions, and 36 healthy volunteers was studied. Samples from 106 patients with bladder cancer and 12 controls were stained for MMP-9. Clinical follow-up data were available on 116 patients (median: 25 months; range: 4-36 months). RESULTS: MMP-9 was present in all urine samples analyzed. There were no differences between patients with cancer and patients with benign disorders. However, patients had significantly higher urinary MMP-9 than normal volunteers (P = 0.0167). Urinary MMP-9 was associated with bladder tumors of advanced stage (P = 0.0065) and large size (P < 0.0001) but not with grade (P = 0.14), multiplicity (P = 0.31), recurrence (P = 0.55), progression (P = 0.83), or survival (P = 0.55). Low MMP-9:TIMP-1 ratios in patients with nonmuscle-invasive tumors were associated with higher recurrence rates (P = 0.0035). Sixty percent (64 of 106) of bladder tumor specimens expressed MMP-9 compared with none of 12 normal urothelial biopsies (P < 0.0001). MMP-9 staining was associated with tumor size (P = 0.014), disease progression (P = 0.005), and poor disease-specific survival (P = 0.022) but was unrelated to tumor stage (P = 0.46), grade (P = 0.26), multiplicity (P = 0.85), or recurrence rate (P = 0.62). CONCLUSIONS: High urinary MMP-9 levels are associated with large bladder tumors. A low urinary MMP-9:TIMP-1 ratio may indicate a higher risk of intraluminal nonmuscle-invasive tumor recurrence and may assist in planning follow-up surveillance protocols.